Software-Defined Networking (SDN) has been one of the major buzz
words of the networking industry for the past couple of years. And
yet, no clear definition of what SDN actually covers has been broadly
admitted so far. This document aims to clarify the SDN landscape by
providing a perspective on requirements, issues, and other
considerations about SDN, as seen from within a service provider
environment.
It is not meant to endlessly discuss what SDN truly means but rather
to suggest a functional taxonomy of the techniques that can be used
under an SDN umbrella and to elaborate on the various pending issues
the combined activation of such techniques inevitably raises. As
such, a definition of SDN is only mentioned for the sake of
clarification.